Nanoscale Investigation of Protein-Surface Interactions

多肽和蛋白质在界面上的相互作用和分子结构在 广泛的生物医学应用(植入生物材料、诊断阵列、细胞培养、组织 工程构造等)。在这里，我们建议开发一套互补的表面 生物分析和计算工具，以提供关于纳米级结构和 多肽和蛋白质与表面的相互作用。初步模拟亮氨酸/赖氨酸(LK)多肽 定义的a-螺旋和b-折叠二级结构将用于开发该工具集。这些表面 研究范围从烷硫醇功能化纳米颗粒到纳米结构底物。这个 这些研究中使用的实验技术将包括固体核磁共振、静态飞行时间二次离子 质谱学，和频产生，近边x射线吸收精细结构，表面等离子激元 共振和x射线光电子能谱。要实现这些实验的全部威力 技术，将开发互补的计算方法来从理论上分析 用分子动力学模拟这些相同体系的吸附行为。把这些放在一起 实验和计算方法将在纳米尺度上提供对 表面结合肽的二级结构、分子取向和侧链/表面相互作用， 以及界面水在多肽/表面相互作用和结构中的作用。然后，这些方法将 扩展到更复杂的生物分子--蛋白质G的纳米尺度表征 这一新的工具集将阐明将多肽和蛋白质附着在 表面在纳米尺度上具有明确的结构，能够在分子水平上控制蛋白质的吸附 和固定。这将在生物应用中产生广泛的影响，因为控制了 表面固定化多肽和蛋白质在纳米尺度上的构象、取向等将直接 影响生物医学设备的生物活性和生物兼容性。 将蛋白质和多肽附着在纳米颗粒表面是一种很有希望的早期策略 癌症的检测和治疗。同样，蛋白质和多肽与生物医学设备的结合 拥有改善这些设备功能的前景。本建议书中开发的工具将 提供以最佳方式将蛋白质和多肽附着到表面所需的理解和信息。

The interactions and molecular structures of peptides and proteins at interfaces play an important role in a wide range of biomedical applications (implanted biomaterials, diagnostic arrays, cell cultures, tissue engineering constructs, etc.). Here we propose the development of a complementary suite of surface bioanalytical and computational tools to provide information at the nanoscale about the structures and interactions of peptides and proteins with surfaces. Initially model leucine/lysine (LK) peptides with well- defined a-helix and b-sheet secondary structures will be used to develop this tool set. The surfaces investigated will range from alkanethiol functionalized nanoparticles to nanostructured substrates. The experimental techniques used in these studies will include solid state NMR, static time-of-flight secondary ion mass spectrometry, sum frequency generation, near edge x-ray absorption fine structure, surface plasmon resonance and x-ray photoelectrdn spectroscopy. To realize the full power of these experimental techniques, complementary computational approaches will be developed to theoretically analyze the adsorption behavior of these same systems using molecular dynamics simulations. Together these experimental and computational methods will provide a comprehensive understanding at the nanoscale of the secondary structure, molecular orientation and side chain/surface interactions of surface bound peptides, and the role of interfacial water in the peptide/surface interactions and structures. Then, these methods will be extended to the nanoscale characterization of a more complex biomolecule, Protein G. The information provided by this new tool set will elucidate the design principles for attaching peptides and proteins on surfaces in well-defined structures at the nanoscale, enabling molecular-level control of protein adsorption and immobilization. This will have wide spread impact in biological applications since controlling the conformation, orientation, etc.of surface immobilized peptides and proteins at the nanoscale will directly effect bioactivity and biocompatibility of biomedical devices. The attachment of proteins and peptides to the surface of nanoparticles is a promising strategy for the early detection and treatment of cancer. Similarly, the attachment of proteins and peptides to biomedical devices holds the promise for improving the function of those devices. The tools developed in this proposal will provide understanding and information needed to optimally attach protein and peptides to surfaces.